A conventional computer entity typically comprises a casing containing a processor, memory, input\output ports, a data storage device, e.g. a hard disk drive or the like, a user interface comprising a video monitor, a keyboard, and a tactile device e.g. a mouse or trackball, for driving a graphical user interface. Such computer entities are well known in the prior art.
One known type of computer entity, is known as a “headless” computer entity (also called a “headless appliance”). Known headless computer entities comprise a processor, one or more data storage devices, input\output ports, and memory, but lack the usual physical console user interface, that is they are not provided with a user console having a visual display monitor, mouse or keyboard. Headless computer entities are not generally intended to be used under direct human control or intervention. A known network attached storage device (NAS) is an example of a known headless computer entity.
Headless computer entities have an advantage of relatively lower cost due to the absence of a user console, and associated hardware for that console. However, because headless computer entities do not have conventional user interfaces for human interaction, and generally do not have ports by which conventional keyboards or video monitors can be connected, this creates specific problems if there should be a disk failure of a headless computer entity in the field, that is, after manufacture and once the computer entity has been commissioned in it's own operating environment.
Failures of headless computer entities in the field may give rise to a manufacturer service callout. A service engineer or a technician has a difficult task in repairing a headless computer entity compared with a conventional headed computer entity having a user interface as s\he cannot install software through Wizards or other operator-interactive installation procedures, because there is no physical, visual or tactile user interface console provided with the headless computer entity.
In a headless computer entity having twin hard disk drives, if a disk drive fails, then data may be lost. In a headless computer entity having multiple disks, there needs to be some sort of scheme to handle disk failure and replacement without the need for human intervention, other than physical replacement of a physical component.